1. Field of the Invention
Polymeric materials have found widespread use in the manufacture of innumerable articles. There is a constant need for additional polymeric materials having new qualities or old qualities at reduced expense. This invention relates to a process for providing additional polymeric materials by means of a grafting reaction. The invention more specifically pertains to a polymeric grafting reaction wherein the reaction is conducted in an internally baffled tube, under conditions which prevent excessive degradation of the initial polymeric backbone structure, and in the absence of free radical initiators.
2. Description of the Prior Art
Grafting reactions, in a general way, are well known. A process for graft reaction of alpha-olefins using derivatives of unsaturated carboxylic anhydrides is disclosed in U.S. Pat. No. 3,236,917, issued Feb. 22, 1966 on the application of Natta et al. That patent discloses grafting in a roll mill or in solution, always in the presence of a free radical initiator.
U.S. Pat. No. 3,862,265, issued Jan. 21, 1975 on the application of Steinkemp et al., discloses a grafting reaction process in a screw-fed extruder device. The process includes working a polymeric material in the extruder to degrade it prior to introducing graft material. The materials are mixed and moved entirely by the action of the screw feed and the reaction is conducted in the presence of a free radical initiator.
U.S. Pat. No. 3,873,643, issued Mar. 25, 1975 on the application of Wu et al., discloses a polymeric material having grafted cyclic or polycyclic acids and anhydrides. The backbond polymers are polyolefins and the grafting reaction is conducted in heated extruders or roll mills.
U.S. Pat. No. 3,884,882, issued May 20, 1975 on the application of Caywood, discloses the preparation of adducts of maleic anhydride grafted onto a polyolefin backbone polymer. The grafting reaction is conducted in extruders or roll mills at temperatures of from 225.degree. to 350.degree. C.